The overall objectives of this project are (a) to isolate and characterize basement membrane related glycoproteins isolated from an extracellular membrane elaborated in cell culture and (b) to study the assembly of these glycoproteins into a model basement membrane. For these studies mouse embryonal carcinoma derived cell line will be used. Studies on the relationship between cytoskeletal elements and adhesion of cells to basement membranes will also be initiated. The techniques to be utilized to approach these objectives will include somatic cell fusion and a variety of immunological and chemical methods.